title: Exploiting pseudo C2-symmetry for an efficient synthesis of the F-ring of the spongistatins.
abstract: A concise and efficient synthesis of the F-ring fragment of the potent antimitotic marine macrolide spongistatin 1 has been developed. The key sequence involves double cross-metathesis/Sharpless asymmetric dihydroxylation reactions to establish four stereocenters in a pseudo C2-symmetric array, followed by a selective protection reaction that breaks the pseudosymmetry, establishes a fifth stereocenter, and effectively differentiates the ester termini. Overall, the six contiguous stereocenters in the C(37)-C(45) F-ring fragment are established in just seven steps.
authors.affiliation: Department of Chemistry, Columbia University , New York, New York 10027, United States.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Tanis
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Infantine
authors.forename: James L
authors.initials: JL
authors.lastname: Leighton
mesh_terms: D018942:Macrolides / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D000095702:Polyether Toxins
chemical_list: D018942:Macrolides; C083856:spongistatin 1; D000095702:Polyether Toxins